John Kisiel, M.D., discusses a recently published article in Alimentary Pharmacology & Therapeutics about serrated epithelial changes in patients with Crohn’s disease and ulcerative colitis.
Patients with inflammatory bowel disease are at an increased risk for colorectal cancer. The risk is increased by how long patients have had the disease, how old they are, how extensive the disease is throughout the colon, and the presence of a liver disease.
Researchers know certain polyps are precursors for colorectal cancer, and look for such polyps when performing routine surveillance colonoscopies to prevent colorectal cancer.
Recently, researchers have identified a type of tissue abnormality seen in patients with chronic colitis called serrated epithelial change or flat serrated change. The tissue is often sampled by random biopsy and has similar features as serrated polyps. The introductory findings of the new tissue among patients with chronic colitis has caused some confusion.
To address the confusion, a retrospective study was performed using patient records from 2006-2012 at Mayo Clinic. Serrated epithelial change was uncommon when looking at nearly 4,000 patients with inflammatory bowel disease (IBD) that had a colonoscopy in a three year period.
The researchers found serrated epithelial change in about 4 per 1,000 colonoscopies per patient. Also, serrated epithelial changes were more likely to occur in high risk patients for developing colorectal cancer. The researchers followed such patients' medical records forward to see how common it was for the patients to be diagnosed with colorectal cancer. They also followed forward a group of control patients. The two groups were balanced with other known risk factors for colorectal cancer such as long standing disease, disease distributed widely throughout the colon, age, sex.
The findings show the group of patients with serrated epithelial change were at an increased risk for colorectal cancer. About a third of patients developed polyps after three years of follow up. However, when the two groups were spilt, the statistical difference was abolished.
There are some important limitations for the study. The study had a small sample size and an inability to study multiple variables.
In conclusion, while the risk of developing a cancerous polyp is high for patients with or without serrated epithelial change, most of that risk was attributed to other factors.
Read the full study online here.
For more information about IBD, visit mayoclinic.org/ibd.
Dr. Kisiel is a gastroenterologist at Mayo Clinic.